A known design of such a cell is a series of planar electrodes suspended in a circulating electrolyte across which a voltage is applied. A membrane is supported to cover each electrode to provide separation of the hydrogen and chlorine gas produced by the electrolysis of the electrolyte, which gases are then separately extracted from the cell.
The heat produced by the electrolysis process is removed from the cell by the circulation of the electrolyte but will still subject the cell components to a range of operating temperatures in a given work cycle.
Such a stack of electrode/membrane components has been formed by stacking a series of frames interposed between the electrodes and membranes to form sealed interfaces with them, and to form common manifolds for transporting the electrolyte to and from the electrodes and membranes of the cell sealing being obtained by applying pressure to the stack by clamping them together. A disadvantage of this approach is that all the seals are, in effect, fully formed at the same time as the pressure is applied to the stack and failure of one seal can mean having to reassemble a large part or all of the structure. Particular difficulty is associated with the formation of the manifold seals a construction requires the components to be manufactured to close dimensional tolerances. Thermal cycling also introduces physical stresses that can prejudice seal security during use of the cell.
Such cells include one or more large-area, thin membranes with no ability to support themselves which must be supported in the cell so as to allow flow through the membrane but not to by-pass it. Provision must also be made to provide flow paths for electrolytes to both sides of the membrane which ensure that the flow of the electrolytes is evenly spread across the area of the membranes and so the area of the electrodes of the cell.